BackTable / VI / Podcast / Transcript #142

Podcast Transcript: Type B Aortic Dissections

with Dr. Frank Arko

Interventional Radiologist Sabeen Dhand talks with Vascular Surgeon Frank Arko about endovascular treatment of Type B Aortic Dissections (TBAD), including patient selection, appropriate sizing, and complications to avoid. You can read the full transcript below and listen to this episode here on BackTable.com.

Table of Contents

(1) How Are Aortic Dissections Classified?

(2) How Are Aortic Dissection Patients Treated?

(3) What Are The Risks and Complications When Treating Patients with Aortic Dissections?

(4) What is the difference between Acute, Subacute and Chronic Phase Aortic Dissections?

(5) What Imaging Modalities Can be Used for Aortic Dissection Workup?

(6) What is the Initial Medical Management for Patients with Aortic Dissections?

(7) What is the Ideal Time Frame to Treat Aortic Dissection Patients?

(8) Tips to Avoid Complications

(9) When to put Lumbar Drains on TEVARS to Prevent Paralysis

(10) Follow Up Care

Sponsored by:

Listen While You Read

Type B Aortic Dissections with Dr. Frank Arko on the BackTable VI Podcast)
Ep 142 Type B Aortic Dissections with Dr. Frank Arko
00:00 / 01:04

Earn CME

Reflect on how this Podcast applies to your day-to-day and earn AMA PRA Category 1 CMEs.
Follow the button below to get started with CMEfy.

BackTable CMEfy button

Stay Up To Date

Follow:

Subscribe:

Sign Up:

[Dr. Sabeen Dhand]:
Hello, everyone and welcome to the BackTable Podcast, your source for all things endovascular and more. You can find all previous episodes of our podcast on iTunes, Spotify, backtable.com or any other podcast platform you enjoy.

[Dr. Sabeen Dhand]:
I'm Sabeen Dhand as your host this week and I'm really excited to introduce our guest today, vascular surgeon, Dr. Frank Arko coming to us from Sanger Heart and Vascular Institute in Charlotte, North Carolina. Welcome, Frank.

[Dr. Frank Arko]:
Well, thanks for having me. It's a pleasure to be here.

[Dr. Sabeen Dhand]:
Oh, the pleasure is ours. I mean, tell us a little bit more about yourself. I mean, how did you develop your passion for aortic work and then land up in North Carolina?

[Dr. Frank Arko]:
That's probably a good little story. I would say that when I went to medical school, I always had sort of a passion for surgery. I wanted to be an orthopedic surgeon or my father said, "You should think about orthopedic surgery." He's a general surgeon. Then when I got into medical school, I did some NIH work on the cardiovascular system. So I really thought I wanted to be a heart surgeon. Then when I went through my general surgery and residency training I really sort of enjoyed vascular surgery more. I really always liked the aorta, mostly aneurysmal disease. And I went off to Stanford where they had a very large sort of aortic practice. That's really why I went there. Very strong team surgeons, vascular surgeons, cardiac surgeons, and radiologists.

The innovation that was going on there at the time was really incredible. I think, I really had it at the right time. I had the opportunity to work with Mike Dake, Charlie Semba, back in the day. A co-fellow of mine as an IR was Rusty Hoffman. I was a vascular surgery fellow and a great team of surgeons. And Craig Miller, Scott Mitchell, Neil Alcott and Chris Aarons. I would say that's really where I developed my sort of knowledge and passion for thoracic aortic disease.

And ever since then, I sort of just really liked it. When I finished my fellowship, I stayed there at Stanford. I stayed on faculty there for about four or five years. I was in the process of developing some stuff with Tom Fogerty, working with a lot of different companies on stent graft designs, mainly Medtronic.

I grew up in California, but I was married - still married. My wife was from Texas. She always really wanted to get back to Texas. So when an academic opportunity came up, I said I'd take a look. So actually one year both in Houston as well as Dallas came open. And the reason I really like Dallas a little bit more than Houston was at the time Houston had a pretty well-developed aortic practice, some very big names that most people around the world know and I wasn't sure I really wanted to get into that sort of competitive environment having to work against some very, very strong names, and very, very good surgeons.

But Dallas didn't really have the same thing. As the academic center, it was a very good academic center. I wanted to test my ability to... I sort of inherited a practice at Stanford from some people that retired or went on sabbatical and I wanted to see if I could build my own sort of thoracic practice. And actually, I was able to do that. Then when I was there between both at Stanford as well as in Dallas, Texas, both places I was in these you know very well-known academic centers, but frankly, I was surrounded by very large systems, in California, in Stanford.

I was surrounded by basically Kaiser, everywhere. Then when I was in Dallas, I was surrounded by Baylor which is now Baylor Scott & White. And that is the largest system in Texas. What I really saw was those two systems were really managing, if you will, the patient population. In an academic center that I was at, I was really obligated to getting whatever the systems that were around me were willing to sort of send my way, which was nice because it allowed me to develop a very sort of complicated practice, but if I really wanted to go to the next level and have a much larger disease process to manage, I really felt that I needed to go into a system.

At the time in Dallas, I was really looking to look for a cheap job. I had some cheap jobs and I interviewed here at Carolinas Healthcare which is now Atrium Health which is part of Sanger Heart and Vascular. When I got here, what I saw was, one, it was a truly collaborative heart and vascular institute. So I had cardiologists - a lot of them. I had some cardiac surgeons and had vascular surgeons. Didn't have IR. The IR is a sort of a separate group and we have a nice working relationship with Charlotte Radiology.

But I really want to sort of be in an institute. And the system, I thought was on the verge of versioning out and getting much bigger. I had some friends in the area that told me they thought that this system was really going to be taking off. I came here and I mean the system has really done everything that I thought it was going to do, and probably even a little bit more than what I thought it was going to do. But the ability to manage, if you will, the aorta from a part of the Carolinas, so the Western Carolinas, part of South Carolina, a little bit of Tennessee, and even a little bit of Georgia, really allows us to put in protocols in place, find the disease quicker, manage it a little bit better, and then follow these patients systemically long-term to try to really improve their long-term outcomes. So that's really how I got here. And I got to tell you, I really enjoy it.

[Dr. Sabeen Dhand]:
That's amazing. That's a lot of big names. That's an amazing way to come into this aorta world, and now you're the aortic guy. I mean, aside from the aorta, you're a man of many talents. I mean, I enjoy seeing all the music you post. I mean, if it wasn't for medicine, would we be seeing you live on stage?

[Dr. Frank Arko]:
Probably not. When I was younger, I loved music. I actually played a lot more music back then. I played in a guitar. I play classical guitars. I play in a classical guitar quartet from probably about the age of eight to about probably about 16, and that's when I veered off into more sort of like punk-grunge type music. I did that all through college. It's actually how I met my wife was really through music. Then medicine really got me away from music. I didn't really play it. I would actually buy instruments. I played piano too. Then I also played drums.

So in the band that we formed, I actually started as the guitarist, but moved over to the drummer mainly because we couldn't find a drummer. Then when I got married and I started having kids and we didn't have much money, and I didn't have much space, my wife sort of made me get rid of a lot of the instruments that I had. There were a few that I just said, "There's no way they're leaving." But I did have to get rid of the drum set and I had to get rid of keyboards and things like that. But then when I started having kids, they got interested in music.

We put them into lessons and stuff, but they just said, "We're not having any of that." They did about two, three weeks of lessons. I grew up playing in lessons all the time. Then they developed a love for it and it brought me back to playing music. So that's what I do. I now have a drum set. Again, you've never seen me play the drums.

[Dr. Sabeen Dhand]:
Yeah. We're going to see that now. We got to see that on a video posted soon.

[Dr. Frank Arko]:
Yeah, soon.

[Dr. Sabeen Dhand]:
Awesome. No, that's great. We'll start our topic about type B aortic dissections, TBAD, if people see we post that acronym online. But how much of your practice is thoracic aortic work?

[Dr. Frank Arko]:
I'd say the amount of thoracic aortic work that I do is probably in about the 15 to 20% range of my entire practice.

[Dr. Sabeen Dhand]:
Okay.

[Dr. Frank Arko]:
If you had to define it as aorta, I'd probably say it's about 30 or 35%.

[Dr. Sabeen Dhand]:
Got it. And then how much of that is open versus endovascular?

[Dr. Frank Arko]:
I'd say that it used to be about 80 to 90% endovascular and about 15 to 20% open. I would say that my open is starting to creep up a little bit more, probably maybe about 75/25. It's probably due the fact that I'm getting referred a lot of complex stuff - sort of failed endovascular stuff. As you've been in it for a long period of time, I've been doing endovascular stuff for, let's see, 20-22 years. So when you've been doing it for 22 years, you start to see the failure mechanisms of some things. And you think that maybe you can get through these things.

To be honest with you, the majority of the time you can get through from an endovascular standpoint, but I would say that I've become a little bit more conservative in the younger, healthier patient with anatomy that's not very conducive to endovascular repair. Maybe doing them open a little bit more, and really having pretty good results with it.

[Dr. Sabeen Dhand]:
Yeah, I know. I'm sure you see some of the most complex and also some really bad failures and definitely open. That's great that your open practice is also increasing. I wanted to start off with some definitions for our listeners, especially for those that are not as familiar with type B dissections. I mean, what are some kind of vocabulary you use to describe type B aortic dissections? What is it and what are some vocabulary?

(1) How Are Aortic Dissections Classified?

[Dr. Frank Arko]
If you're going to talk about dissections, I would talk about first Type A and Type B. I think that's one that you need to understand. I think that's makes it relatively simple. I went to Stanford so I'm going to use just the Stanford and not the DeBakey. I think the DeBakey is a little bit more difficult to understand and define. I really focus on the on the Type B and and maybe the residual Type B following the type A. It's just a difference in where the the tears occur.

So I train a lot of fellows and residents, and I get to be a little bit of a stickler in some of the nomenclature for the repairs. Often times, when someone's younger and talking to you about a dissection, they're like, "Well, I got a symptomatic dissection, or I got a symptomatic dissection with a lot of pain." The first thing I said, "If you're going to get into the world of dissections, the first thing you need to really talk about is the complicated versus the uncomplicated.

Now, you can get into a whole lot of definitions about whether those are even good terminology. And to be honest with you, I have some problems with the complicated versus the uncomplicated nomenclature. But I think that is most important. The uncomplicated really, they just have a dissection and they don't really have much in the way of anything else causing them a problem.

I think the number of those patients that have the truly uncomplicated dissection, I think they're there, but they're relatively infrequent when you really start to take a look at the imaging and how the patients are being managed. I find that there are a number of complicated dissections that would get downgraded, if you will, into the uncomplicated in patients who have ischemia to a kidney.

I see this one all the time. Basically, there's low flow to one of the kidneys. Typically it's the left. The patients are being managed, but now they're on four or five antihypertensive agents. They're pain-free. The creatinine has gone from normal 0.9 to 1.3-1.4 and then they're sort of downgraded in this uncomplicated dissection. Now, are they as complicated as someone who's got occlusion of the SMA? No. It's not an emergent procedure, but probably should be managed because of the long-term effectiveness of therapy and whatever that therapy may be, whether it's TEVAR versus TEVAR plus or minus a petticoat versus TEVAR with a renal stent. The older I get, I tend to be a little bit more aggressive in managing the visceral arteries, visceral renal arteries in those complicated dissections to try to improve the long-term outcomes of those patients. So I think that's really the biggest key.

Then you take your uncomplicated, and you take a high risk category. So size of the aneurysm - Is it greater than 4 or 4.5? What's the size of that true lumen versus the false lumen, the ratio, the size of the false lumen? If it's greater than 22 millimeters, that portends a worse outcome. Then those high risk features, we have a tendency to really treat those patients a little bit earlier than later.

(2) How Are Aortic Dissection Patients Treated?

[Dr. Frank Arko]
I think the problem with treating these patients is you have to weigh the risk benefit ratio. When you look at that, there's three things that they take on when you fix them from an endovascular standpoint, right? So there's good data to show that medical management is probably better than emergent surgical therapy. There is good data. The mortality is just too high with open surgical repair.

There's not a great randomized prospective study comparing medical therapy versus TEVAR. There's data that really didn't show much in the early phase, but there's probably an improvement in the long-term outcomes of those patients, basically the INSTEAD-XL trial.

(3) What Are The Risks and Complications When Treating Patients with Aortic Dissections?

The problem with treating the patients and where everyone's concerned comes from is these three risk factors when you fix them. Retrograde Type A dissection, which basically turns you into medical therapy, now a sternotomy. There's a risk of stroke when you treat them. I think depending on the zone that you're treating, who's treating them, how many you've treated. That risk will vary probably somewhere between four to eight to 10%. Those strokes typically are not major disabling strokes, they're typically minor non-disabling strokes, but they're still strokes and we don't know the long-term outcomes of those. Then lastly the risk factor that everyone is greatly concerned about is spinal cord ischemia, paralysis. And to me, the worst of those three is really paralysis.

I mean, non-disabling stroke is bad. If you've got a retrograde dissection and you manage it from a team standpoint, you've always got a cardiac surgeon on board involved. You have to have that for that complication. Then I think the mortality or the bad outcomes from that is not terrible. I mean, if you catch it early, they can be repaired and fixed and they usually do okay.

Spinal cord ischemia and paralysis, I mean that is just a dreaded complication. It's happened to me. It's happened me with open surgery. It's happened to me immediately after. It's happened to me delayed for four weeks after I did TEVAR. And the problem with that is if they get permanent paralysis, it really is just a very, very tough way to live for someone who's older. And the risk of mortality long-term in those patients is relatively high, especially in the first six months after.

If we can figure out how to minimize or eliminate those three sort of major complications, then I think you can get into the role of everybody that has a dissection type B should maybe undergo TEVAR, but until we can sort of eliminate those or minimize those three things, that's why you will, I think, continuously have this argument over medical therapy, optimum medical therapy versus early TEVAR whether it's in the acute phase, the subacute phase, or the chronic phase.

(4) What is the difference between Acute, Subacute and Chronic Phase Aortic Dissections?

[Dr. Frank Arko]
As a surgeon who who sees more the chronic. Acute, so in the first 14 days, gets a sub-acute and that definition changes. So depending on inclusion, exclusion criteria or varying guidelines, it could range from 14 days to 30 days or up to 90 days. Then you got the chronic, which is longer than that. The problem with those definitions as well is because they start to talk about the lamella or how the tear is and what you can do from the endovascular standpoint versus open surgery is then getting into that chronic dissection.

So I want to treat the early stuff to try to minimize someone getting to the chronic phase. That chronic phase in which it becomes the dissection that has now become aneurysma from an endovascular standpoint really becomes a complex repair no matter who's doing it, and even if you've done a lot. The reason for it is, is the top part is all the same. Nothing changes. It's cover the entry tear. You typically have a normal neck. Maybe you've got to cover the left subclavian. Maybe you've got to do a bypass or revascularize the left subclavian. However, you want to do it, whether it's with a fenestrated graft, in situ repair, or surgical bypass. The problem gets on the bottom side.

And when you come to the bottom side, sometimes I think you almost take the chronic dissection that's been slowly getting aneurysmal because you got the inflow and then you got re-entry tears down at the bottom. Sometimes when you go in with the chronic phase, you go up to the top, you cover the entry tear, but you don't have any ability to fix the stuff on the bottom. When that happens, I think in a select group of patients, you get this entry flow, but is now on the bottom.

You start to see this a little bit more rapid increase in size of the thoracic aorta. So then you got to get in that more complex repair of a four vessel fenestrated graft. That becomes a very difficult repair in anyone's hands. I think what happens if we can treat those earlier ones, we minimize those operations that are needed in the chronic phase and what happens is in the chronic phase, you never eliminate the three risk factors that you take, if you fix them early.

You still have that risk of stroke, you still have that risk of retrograde, and you still have the risk of spinal cord ischemia. So that's why I like to treat more and more type B's earlier to eliminate that risk of needing that more difficult complex repair. I think most large institutions can treat and treat well the type B aortic dissection, which certain protocols and instructions, and doing it as a team system. When you get in that more complex repair, that type 2 thoraco-abdominal, which is from the dissection, that I think is probably limited to about 15 to 20 centers, maybe more. Within the US, that actually can really do it well.

The problem with that is just patients like this all over the United States trying to seek places to go and then they can't afford to get where they need to go and they want to do it wherever it's being done. Maybe physicians can say, "Oh, I think I can do it, but I haven't done that many, but patients want to do it." I think you get into issues with outcomes specifically mortality and spinal cord ischemia and in those patients being treated at not large volume centers.

[Dr. Sabeen Dhand]:
Yeah. I mean these cases can be real complex. A simple type B, sure that can be easier to fix, but these complex ones should not be treated at a low volume center. You mentioned a lot of vocabulary. So that's great. I mean, we're going to touch base on all of that. You mentioned entry tears. Your workup, I think all of us agree that the CTA is kind of your main work up on a type B dissection. Is there any other imaging modality used like echo or MRI?

(5) What Imaging Modalities Can be Used for Aortic Dissection Workup?

[Dr. Frank Arko]:
I don't use much in the way of MRI or MRA. I do get echoes on every patient that has a dissection. You've got to make sure that the aortic valve is okay. You can take a look a little bit at their a setting, take a look at what the diastolic and systolic function of the heart is. You can look and see if they've got left ventricular hypertrophy. When I treat the patients, the only other imaging that I tend to get is IVUS in all my patients, which helps me identify what the flap is, make sure I'm not in the false lumen when I want to be in the true lumen. Those are the three main imaging studies that I get.

(6) What is the Initial Medical Management for Patients with Aortic Dissections?

[Dr. Frank Arko]:
Sure. So when we get someone, we will typically admit them to an ICU. We've got a very good working relationship with our pulmonary critical care team. We tend to use just the AHA guidelines. So the first thing we want to do is actually drop the heart rate down. We try to get in the 60 range if we can. That's typically managed with esmolol. And then for the blood pressure, we want to get that down typically in about the 120 systolic range if we can. We'll use esmolol for that if we need. As a secondary drug, we will tend to use Cardene.

Now, the one thing that we will do when we initiate that, and we've we'd probably treat about 70 to 80 dissections on a yearly basis is we want to try to start initiating oral medications on those patients as soon as possible. We will typically go with a beta blocker, calcium channel blocker, the Norvasc, and then an ARB or an ACE inhibitor. The one important thing to remember is trying to be that aggressive with the medical therapy is there are some patients who just cannot tolerate that blood pressure because they've just been used to a much higher blood pressure.

So they'll get some cerebral hypoperfusion. You might start to see them become a little bit confused. You might actually start to see their creatinine rise. And if you see that stuff, then you really need to lighten up on the medications. That would be also another indication for us to treat those patients a little bit earlier so that we can relax on the blood pressure medications.

Pleural effusion worries me. They tend to typically have a pain with that. I don't think that they're at any real risk of rupture unless the size of the aneurysm is getting bigger, and you can't control their pain, and they have a pleural effusion. Then I get a little bit more worried. I see a lot of patients who I can get into that sort of no pain with relatively easy medical therapy that may still have pleural effusion. And that pleural effusion will typically go away.

Now, if the size of the aneurysm is big and it's 4.5 or 5, then I get a little bit more concerned that they're going to be at some sort of impending risk of rupture. It's relatively rare but I think it can occur.

(7) What is the Ideal Time Frame to Treat Aortic Dissection Patients?

[Dr. Sabeen Dhand]:
And when you talk about treating patients earlier, I mean that's the big debate for non-hard indications like rupture or malperfusion. When is your ideal time frame that you like to treat these patients? Is it three days, 10 days, two weeks? Maybe someone who has some of these high-risk clinical features, but is otherwise... Well, as we said, they fit in that zone that's complicated.

[Dr. Frank Arko]:
Yeah, if they're in the complicated section, then I tend to treat them relatively quickly. It would depend on the level of the complicated section. So for me, if they've got leg ischemia, SMA ischemia, or spinal cord paralysis, you're going to get an operation right away. If you're coming in and you've got a rising threat and you've got some sort of low flow to that left kidney, I'm probably going to treat you at about the five to seven-day range. That would be the complicated dissection. Of course if they're ruptured, that's immediate. If you're getting someone who's coming in they got uncomplicated dissection, but they have high risk features.

So large false lumen. If they have continued pain, I think they need to be treated before they leave. If their aneurysm is probably greater than five or so, I have a tendency to treat them a little bit earlier. We evolve this sort of on a constant basis. A lot of it's based on data. If you take a look at the data that's out there, if you treat them in the more acute phase or hyper acute phase, you have a little bit higher risk of having some complications, mainly the retrograde type A dissection I think it's the biggest one.

So we like to try to get them normotensive, non-pain free, out of the hospital if we can and then we will try to treat them at about four to six weeks or really after 30 days. You start to take a look at all sorts of different stuff. So we're looking at readmission rates within 30 days for patients. Every physician is looking at that. Every hospital is looking at that. One of our biggest readmission rates is actually the type B dissection in which we manage medically, discharge home and then they come back three, four days later because now they're having pain.

If you come back with pain, we're then going to treat you. But those patients are typically the patients that have some high risk features like we mentioned. So I would say I, and we as a group are tending to become a little bit more aggressive in those high risk patients and treating them earlier before discharge rather than later.

(8) Tips to Avoid Complications

[Dr. Sabeen Dhand]:
That aorta and that acute phase is fragile and you mentioned, the retrograde dissections are what you worry about among other things. In a patient who you have to treat acutely, they're coming in, they have rupture or amount or malperfusion that's that's requiring treatment then and there, what are some tips that you do that you try to avoid the complications like a retrograde dissection or stroke? Do you get in and out? Do you do just TEVAR? Do you dabble in the petticoat in that or use any adjunct techniques?

[Dr. Frank Arko]:
I think those are great questions. I think it's a little bit depend upon what I'm seeing when I get in there. I think that if you've got the complicated dissection, I think about 15 to 20% of those patients will need some sort of adjunctive techniques. I guide everything as I go in. So I don't go into the procedure saying, "I'm going to do these five things." I start in the process of what I'm going to do, re-image, and then decide what needs to be done next.

So if you come in, I need to treat you hyperacutely. First, I want to get your blood pressure appropriate. So appropriate anti-impulse therapy. Depending on the level that I have to go up to. So if I have to cover left subclavian, I may or may not pace you. So I like to deploy under pacing. I just think it can be a little bit more accurate. We do some Type A dissections as well with TEVAR and some ascending work. So getting the ability to do TEVAR before you have to get to that stage and understanding how to do it, I think is a nice bridging to get to the next level if you want to go into zone one or zone zero.

So pacing I think is sometimes important. Two: IVUS through the case. So pre, post, and then deciding what you want to do next. To minimize that risk of retrograde type A dissection, I typically will tend to base my imaging off of IVUS. And again, if it's hyperacute and they come in with a blood pressure like 220, the thoracic aorta is much bigger. So I think you tend to oversize too much. So when you get them an appropriate anti-impulse therapy, you go back in there by IVUS. Their aorta is maybe 30, 31 rather than 40 or 42 when they come in.

So we can then decrease the size of the stent graft. Because if you're putting in, 40, 42 stent grafts in dissections, you really raise the risk of retrograde Type A dissection. So I think IVUS is important. When you come in and you talk about petticoat, I think there's certainly a need for petticoat in certain patients which is typically when the true lumen remains completely compressed through the visceral segment and the infrarenal. There have been sometimes maybe once a year and this is pre the petticoat when it was FDA approved. So it was approved outside the US first where we would have to put stents through that visceral segment to get it open.

But I'd say it's like 1 or 2% for that. I find that if we just go up do the TEVAR, we get pretty good expansion of the true lumen all the way through the visceral segment. We tend to be a little bit more aggressive in the amount of thoracic coverage that we do and this has again been a little bit of my own evolution over 22 years where I used to go in, put one piece. You hear people talk about it. So I just put in a single 10 piece for the TEVAR. I cover the entry there.

I used to do that but then I'd be back at six to eight weeks because it'd have aneurysmal degeneration distal to that because I was deploying in the still disease segment through the mid thoracic aorta that talk about stent graft induced new entry tears. It's not from stent grafts, it's just disease. So I now have a tendency to go further down. I tend to go about two to three centimeters above the celiac. You get into more normal aorta. I think you also get much better aortic remodeling, thoracic, long-term but then you bring in a little bit of risk of increased spinal cord ischemia.

We haven't really seen that there, but we certainly have it. We can usually recover it, but the data in China in which they've got a lot, when they've gone down that far ahead slightly increased risk of spinal cord ischemia. So when you become a little bit more aggressive, you have to manage that complication. Then once I do that, then I take a look at the visceral segments sort of see what's going on. I tend to be a little bit aggressive on treating the viscerals in the renals.

So if I see something that's even a little bit dynamic obstruction or if you have a static obstruction, I'm going to treat you for sure, but I will typically go in and put in a stent. I like to use covered stents in those areas. One, the vessels are big. They track easily. But with the covered stents, there's usually some fenestrations there that you can cover and you can sort of get better aortic remodeling if you can shut off that reentry flow into the false lumen off of visceral or a renal.

Then lastly if I had to, I put a petticoat in but that's like one, two, three, maybe at most 4% for me. I think there's more and more people putting it in. Maybe it's fine. Maybe I'm missing the charge on that one a little bit. But in my own practice, I haven't really felt the need to use it.

[Dr. Sabeen Dhand]:
What about in patients the more the subacute and chronic ones? Are you using the petticoat or stable technique more often in those patients or just in general? Pretty much, you're able to stent usually above the celiac and you'll be okay

[Dr. Frank Arko]:
I usually will start first just to the celiac and then even in the chronic ones. I'll just go to the celiac and see what I get and then follow them back at four to six weeks if they have a tendency to have increased flow or it's getting worse. I'd say it's about that 10 or 15% where it's just going down the ceiling that doesn't work. I tend to do more of a branched repair, got it, because it's just so many multiple fenestrations. I think if you put an uncovered stent down to that area, you're still going to have flow through those fenestrations. I don't know that you're going to get expansion of that true lumen, when it's chronic.

[Dr. Sabeen Dhand]:
And that flap becomes so thick, and when it's chronic, I mean, I'm sure you've seen that even your open repairs. It like becomes leather. So how much is this low radial force, uncovered stent really going to help in those really chronic ones too. We've talked about IVUS and sizing. So you mentioned not to oversize too much. Is there a percentage that you keep in your head as far as how much you just try to be one to one? Do you try to oversize or do you undersize?

[Dr. Frank Arko]:
Well, I think the whole definition of how you actually size becomes important as well.

[Dr. Sabeen Dhand]:
Yeah, how do you do it.

[Dr. Frank Arko]:
I tend to be on dissections that tend to be a little bit more inner wall to inner wall because I want to just cover the entry tear. It's not aneurysmal disease. You typically don't get endoleaks on the proximal neck if you've got enough coverage. So I tend to be inner wall to inner wall. If it's the acute like I said, I tend to go off the IVUS. The problem with IVUS, when you get up in that arch, you've got a pretty big curve and you get more of an elliptical structure rather than a true, orthogonal angle.

I'll look at the minor axis of that IVUS image, and then I look if I had a repeat CT scan after the acute one, then I'll sort of compare that to the CT scan if it's looking like that's 31 and my minor axis is 31. Then I'll go with a device that's probably... And again, it depends on the device that you have. I'm not a huge fan of one-to-one sizing. So if it measures 30, I don't know that I really like putting a 30 graft in, but I probably put like a 32. Just so I got like a little bit under 10% oversizing.

The problem with the one to one sizing is you get a nice repair there, but in some of these patients, when they're discharged and there's a sub select group of patients that get dissections that are typically from illicit drug usage. So whether it's cocaine, methamphetamines, this becomes actually a... It's sort of an interest of mine. But what I see is I bring them in and I treat them with anti-impulse therapy. Their aorta goes down to this 31, 32. I go put in a 32, 34 graft in there and they do great. Then I discharge them home and they're doing good.

Then at six weeks, eight weeks, they relapse with the drug usage. They come back in and now they're having another hypertensive crisis at 220, 230, 240. When you scan them with a CTA, which it looks like is it looks like I grossly undersized my endograph because I had a CT scan that was 31, 32. I put this 32, 34 and now I'm being called on this. I've got a huge type 1 endoleak and all these things because that arch and the ascending order have gone back up to 41, 42 millimeters and it's sort of just leaking all around my graph.

I don't have to intervene, I just have to treat them with anti-impulse therapy. When I do that and rescan them, the aorta goes back to normal and then everything looks okay. So I don't know what's worse, putting in a too large a graft, taking on the risk of a retrograde dissection or sizing it the appropriate size and having to worry about that risk of the drug usage again.

I've tried to get a social work type look at these patients with that repetitive use of drugs to take a look and try to get them into some sort of rehab program. This is not my expertise, but something that we can try to minimize that recurrent risk over and over. I would say I probably have about 40 or 45 of these patients.

[Dr. Sabeen Dhand]:
Really?

[Dr. Frank Arko]:
Well, if you take a look at over 11-year period, that's only four patients per year, but they're recurring. And then the other thing is those are the ones that have a tendency that after a certain number of those occurrences, they start to have really bad problems, a graft infection. Those are ones where you maybe get an erosion into the bronchus, an erosion into the esophagus and they become really, really difficult to manage either from an endovascular standpoint or with a surgical standpoint. So I've been trying to do more and more education on these. I've actually written papers on the presentation of those patients, but they are much much more difficult group of patients to manage.

[Dr. Sabeen Dhand]:
Yeah. I mean, you've definitely seen it all. I mean, that's an interesting select patients there that you have this recurrent problem you have to keep on fixing. We've touched base on the feared complication of paralysis. I mean, are you putting lumbar drains on all of your TEVARs pre or post or what's your approach?

(9) When to put Lumbar Drains on TEVARS to Prevent Paralysis

[Dr. Frank Arko]:
I'm a selective drainer of the spinal cord. There's one group that I put in everybody and that's the type 2 thoraco- abdominal aneurysm, which I'm basically covering from the left carotid down to the iliac bifurcation. Unless that patient is symptomatic or ruptured, that's the case that I tend to stage. So I tend to just do some EVAR work, some work up at the top like basically an elephant trunk. Then when I connect those two grafts as the third stage, that's when I put the spinal drain in because I will have taken out their entire thoracic aorta.

The only other patient that I might do that is someone who's got a combined thoracic aneurysm and an infra-renal aneurysm, but I'm not treating them both at the same time, but I'm going to treat the thoracic. Those are ones that I would probably routinely drain their spinal cord. The rest I tend to be a selective drainer of the spinal cord. I think however you choose to do it is dependent upon where you work and the type of teams that you have involved.

So when you're getting into the management of dissections, remember I'm sort of managing, I diagnose you. I manage you acutely. I treat you with a TEVAR and then I follow your repair. But I have to have a whole another set of teams sort of managing you from when you come in. So I'm not really managing you from a critical care standpoint, I'm surveying you, but I'm not really managing your hypertension. So I've got cardiologists for that.

Then you have these sort of dreaded neural complications. So I've got a team of neurosurgeons that will put the drain in if I treat you selectively and I have a problem, they'll treat it. But if I'm putting the drain in preemptively, I typically have anesthesia, put it in. If they come in and they're on aspirin or Plavix, and I treated you selectively, I then have to get neuro interventional radiology to put in the drain under guidance because they're the ones that are most willing to do that with the two anti-platelets on board to minimize that risk of epidural hematoma.

So there's all these sorts of things that you have to think about. So when you've got protocols in place and you've got service lines on board with those protocols, I think you can be a selective drainer. If the volume of cases that you're doing is let's say one a month, then you're probably better as an institution to be more of a routine drainer rather than having to call someone at 2:00 in the morning to put in a drain that you've never had to call before. So I think it's dependent upon volume, your system and the teams that you can develop as to how you want to manage the spinal cord.

[Dr. Sabeen Dhand]:
Got it. That's good advice, especially for low volume centers. I mean, my center, we're a low volume and the types that we treat are pretty straightforward, but we are a routine lumbar drain facility. We just do that, but it's really nice that you've been able to do so much and that being able to selectively drain, you can avoid a lumbar drain in some of these patients. What about connective tissue disorders? So let's say Marfan. Someone comes with a type B there. Is that someone, are you going to treat endovascular? Are you straight only surgical there? What do you do?

[Dr. Frank Arko]:
I've done both. I think when you get into connective tissue disorders, I think that the data would say that you should try to avoid endovascular repair. I think endovascular repair can be a component of connective tissue disorders, specifically Marfans. If they've had prior surgeries and then you can go stent grafts through from graft to graft. Then you can sort of minimize that risk of the stuff in between.

I got to tell you I've had some very good results in some type B dissections in patients with Marfans, but they already had their ascending repaired. But I've seen some pretty bad failures of stent grafts within connective tissue disorders. There's just a lot of radial force there. If I tend to do it, I would probably use more of the Gore grafts for connective tissue disorders. I tend to be Valian/ Medtronic stent grafts, but those are the two that I mainly use.

But connective tissue disorders, I think there's a little bit less radial force with the Gore graft and creating some complications of dissections. I think if you take someone who's got Marfans and you put in a graft for a type B, I think you run a very high risk of a retrograde type A dissection.

[Dr. Sabeen Dhand]:
Yeah.

[Dr. Frank Arko]:
And even for aneurysmal disease, it'll work for a while, but then you'll sort of get this expansion. Then where the seal zones are, the aorta will get just a little bit looser and you'll have a tendency to get some leaks proximal or distal.

[Dr. Sabeen Dhand]:
Yeah. Then you go on that ever ending, trying to fix all these problems. So speaking of people that you do treat, I mean follow-up wise, are you getting a CT before they're discharged? And then how often are you following them from an imaging surveillance standpoint and then clinically?

(10) Follow Up Care

[Dr. Frank Arko]:
I think it's good. I think if they're a complicated section that I treat, I have a tendency to get a CTA before discharge just to make sure I've got everything fixed up and looks good. If it's more of an uncomplicated dissection that I treat, maybe I treated it at three weeks, four weeks down the road. I tend not to get the CTA prior to discharge. I then tend to get them a CTA at six weeks. And if it looks okay at six weeks, depending on what I see, actually for my dissections, I tend to be about every six month CTA.

If I get you out to a year and you've got very good remodeling, your thoracic aorta is remodeled, but maybe you still have just a little bit of dissection through the visceral segment. But it's frankly not that big or it's a little dilated 31, 32. I then just tend to follow you on every 12-month basis.

[Dr. Sabeen Dhand]:
Okay, that's good. Then these adjunct techniques, I mean, how often now in your experience are you going back and treating the false lumen and things like that? I mean, is it happening often or your technique has improved to a degree that it's not happening as much?

[Dr. Frank Arko]:
I think it depends. I'd say it's about 10 to 15% of patients where I have to go in and do some further therapy. That therapy can be endoluminal therapy of the false limit, which I do, but I don't know that we have any sort of real good techniques to do it. Basically, I've given the same talk with Mike Dake and he goes up there and says, "She's throwing the kitchen sink at the false lumen."

You don't really have any sort of therapy for the false lumen. We attempt to figure things out, which is a lot of what IR has done throughout their entire career. Let's figure out what we can do, and I think that's very helpful. I think for the false lumen the industry has not done a very good job in trying to develop tools for managing it, but I think they will with time. I think the reason is, is because they're still trying to develop the market for the type B dissection.

So they're not seeing the numbers of complications that you have unless you're a high volume center. So long term about 10, 15%, probably going to go higher than that as patients live longer. I find it typically occurs more in those patients who just fail to manage their hypertension and that distal segment just grows. Again, you can get in the branch vessel technology. You can get into false lumen therapy, which will maybe occasionally work but probably going to work for 2-3 years.

And that's coils, plugs, making your own plugs, and then just throwing stuff up there in the hopes that it's going to thrombose off. But I think the best way to manage is just complete reconstruction of that visceral, infra-renal aorta. Again, whether it's open surgery, combination of open surgery, and endovascular techniques or just a pure endovascular management for it.

[Dr. Sabeen Dhand]:
Yeah. I mean, you got those BEVARs and all kind of complex - that we won't go into today, but Frank, this is awesome. I mean, I think this is a really great overview of type B aortic dissections. There's so much more that we can cover and go into more detail that I think we should do as a follow-up sometime and go more into the complex stuff. But we really, really, really enjoyed having you today. Thank you so much. I learned a ton.

[Dr. Frank Arko]:
Okay. Well, you're welcome, and thanks for having me.

[Dr. Sabeen Dhand]:
Yes, of course, of course. Thank you.

Podcast Contributors

Dr. Frank Arko discusses Type B Aortic Dissections on the BackTable 142 Podcast

Dr. Frank Arko

Dr. Frank Arko is a practicing Vascular Surgeon and the Chief of Vascular and Endovascular Surgery at Sanger Heart & Vascular Institute in Charlotte, North Carolina.

Dr. Sabeen Dhand discusses Type B Aortic Dissections on the BackTable 142 Podcast

Dr. Sabeen Dhand

Dr. Sabeen Dhand is a practicing interventional radiologist with PIH Health in Los Angeles.

Cite This Podcast

BackTable, LLC (Producer). (2021, July 16). Ep. 142 – Type B Aortic Dissections [Audio podcast]. Retrieved from https://www.backtable.com

Disclaimer: The Materials available on BackTable.com are for informational and educational purposes only and are not a substitute for the professional judgment of a healthcare professional in diagnosing and treating patients. The opinions expressed by participants of the BackTable Podcast belong solely to the participants, and do not necessarily reflect the views of BackTable.

Up Next

Treating False Lumen Perfusion in Chronic Aortic Dissections with Dr. Daniel Han on the BackTable VI Podcast)
Declots with the Argon Cleaner Device with Dr. Sabeen Dhand on the BackTable VI Podcast)
Neurovascular IR (Part I) with Dr. Sabeen Dhand and Dr. Venu Vadlamudi on the BackTable VI Podcast)
Neurovascular IR (Part II) with Dr. Sabeen Dhand and Dr. Venu Vadlamudi on the BackTable VI Podcast)
New Tools to Treat Severe Distal Femoropopliteal Disease with Dr. John Rundback on the BackTable VI Podcast)

Articles

Aortic dissection complications during treatment

Aortic Dissection Complications During Treatment

CT of aortic dissection types

Aortic Dissection Types

Topics

Aortic Dissection Condition Overview